Citation Nr: 21032093 Decision Date: 05/25/21 Archive Date: 05/25/21 DOCKET NO. 17-46 620 DATE: May 25, 2021 ORDER A rating higher than 70 percent for posttraumatic stress disorder (PTSD) is denied. A rating higher than 20 percent for type 2 diabetes with nephropathy, erectile dysfunction, and right lower extremity peripheral vascular disease is denied. A 30 percent rating, but not more, for diabetic retinopathy is granted. Service connection for hypertension is denied. FINDINGS OF FACT 1. The severity, frequency, and duration of the Veteran's posttraumatic stress disorder (PTSD) symptoms did not more closely approximate both total occupational and total social impairment. 2. The Veteran's diabetes mellitus required only restricted diet and one or more daily injection of insulin during the period on appeal. He had noncompensable complications including nephropathy, erectile dysfunction, and right lower extremity peripheral vascular disease. His symptoms associated with peripheral neuropathy of the bilateral upper and lower extremities were consistent with the existing ratings for these disabilities. 3. The Veteran's diabetic retinopathy manifested as scotoma and visual field loss with average concentric contraction of no less than 31 degrees in either eye, but no other visual impairment as his corrected visual acuity was consistently 20/40 or better and he had no impairment of muscle function or associated incapacitating episodes. 4. The Veteran's hypertension was not shown as chronic in service and did not manifest to a compensable degree within the applicable presumptive period; continuity of symptomatology is not established; and the disability is not otherwise etiologically related to an in-service injury or disease. CONCLUSIONS OF LAW 1. The criteria for a rating higher than 70 percent for posttraumatic stress disorder (PTSD) have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.7, 4.126, 4.130, Diagnostic Code 9411. 2. The criteria for a rating higher than 20 percent for type 2 diabetes with nephropathy, erectile dysfunction, and right lower extremity peripheral vascular have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.3, 4.119, Diagnostic Code 7913. 3. The criteria for a 30 percent rating, but not more, for diabetic retinopathy were met. 38 U.S.C. § 1155, 5107; 38 C.F.R. §§ 3.321, 4.1, 4.75-4.79 Diagnostic Codes 6006. 4. The criteria for service connection for hypertension are not met. 38 U.S.C. §§ 1110, 1112, 1113, 1131, 1137, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from June 1961 to August 1970. The Veteran died in December 2018, and the appellant, his surviving spouse, has been properly substituted. This matter comes to the Board of Veterans' Appeals (Board) on appeal from June 2012 and January 2013 rating decisions of a Department of Veterans Affairs (VA) Regional Office (RO). The June 2012 rating decision granted service connection for posttraumatic stress disorder (PTSD). The Veteran initiated an appeal of the initial rating assigned with a February 2013 notice of disagreement. The January 2013 rating decision granted service connection for diabetic retinopathy, granted special monthly compensation (SMC) based on loss of use of a creative organ, denied service connection for hypertension, and denied the Veteran's claim for a higher rating for type II diabetes. In a February 2013 notice of disagreement, the Veteran initiated an appeal of the ratings assigned for diabetic retinopathy and diabetes and the denial of service connection for hypertension. In August 2017, the RO issued a statement of the case on all four issues. The Veteran perfected his appeal with a September 2017 VA Form 9. In January 2019, the Board dismissed this case due to the Veteran's death. His surviving spouse has since been properly substituted. In April 2020, the Board remanded this case for further development. Increased Rating 1. A rating higher than 70 percent for posttraumatic stress disorder (PTSD) The Veteran was originally granted service connection for PTSD in June 2012 rating decision. At that time, this disability was assigned a 70 percent rating effective August 15, 2011. The March 2021 rating decision granted a total disability rating based on individual unemployability due to service-connected disability (TDIU) based on the impairment associated with his PTSD alone. TDIU was granted for the entire appeals period. Under the General Formula for Mental Disorders (General Formula), the Board must conduct a "holistic analysis" that considers all associated symptoms, regardless of whether they are listed as criteria. Bankhead v. Shulkin, 29 Vet. App. 10, 22 (2017); 38 C.F.R. § 4.130. The Board must determine whether unlisted symptoms are similar in severity, frequency, and duration to the listed symptoms associated with specific disability percentages. Then, the Board must determine whether the associated symptoms, both listed and unlisted, caused the level of impairment required for a higher disability rating. Vazquez-Claudio v. Shinseki, 713 F.3d 112, 114-118 (Fed. Cir. 2013). The issue in this appeal is whether the Veteran's associated symptoms caused the level of impairment required for a disability rating of 100 percent. The Board concludes that the Veteran's symptoms did not cause the level of impairment required for a disability rating of 100 percent. The Veteran's symptoms more closely approximated the symptoms associated with a 70 percent rating, and resulted in a level of impairment that most closely approximated the level of impairment associated with a 70 percent rating. A noncompensable rating is assigned when a mental condition has been formally diagnosed, but symptoms are not severe enough to either require continuous medication, or to interfere with occupational and social functioning. A 10 percent rating is assigned when mild or transient symptoms which decrease work efficiency and ability to perform occupational tasks only during periods of occasional stress, or symptoms controlled by medication cause occupational and social impairment. A 30 percent rating is assigned when symptoms such as depressed mood, anxiety, suspiciousness, panic attacks (weekly or less often), chronic sleep impairment, or mild memory loss (such as forgetting names, directions, or recent events), cause occupational and social impairment with occasional decrease in work efficiency and intermittent periods of inability to perform occupational tasks (although generally functioning satisfactorily, with routine behavior, self-care, and normal conversation). A 50 percent rating is assigned when symptoms such as flattened affect; circumstantial, circumlocutory, or stereotyped speech; panic attacks more than once a week; difficulty in understanding complex commands; impairment of short and long-term memory (e.g., retention of only highly learned material, forgetting to complete tasks); impaired judgment; impaired abstract thinking; disturbances of motivation and mood; or difficulty in establishing and maintaining effective work and social relationships cause occupational and social impairment with reduced reliability and productivity. A 70 percent rating is assigned when symptoms such as suicidal ideation; obsessional rituals which interfere with routine activities; intermittently illogical, obscure, or irrelevant speech; near-continuous panic or depression affecting the ability to function independently, appropriately and effectively; impaired impulse control (such as unprovoked irritability with periods of violence); spatial disorientation; neglect of personal appearance and hygiene; difficulty in adapting to stressful circumstances (including work or a worklike setting); or inability to establish and maintain effective relationships cause occupational and social impairment with deficiencies in most areas, such as work, school, family relations, judgment, thinking, or mood. A 100 percent rating is assigned for total occupational and social impairment, due to such symptoms as: gross impairment in thought processes or communication; persistent delusions or hallucinations; grossly inappropriate behavior; persistent danger of hurting self or others; intermittent inability to perform activities of daily living (including maintenance of minimal personal hygiene); disorientation to time or place; or memory loss for names of close relatives, own occupation or own name. VA and private treatment records, the May 2012 VA examination, his son's March 2012 statement, and the Veteran's lay statements show that the Veteran's PTSD was manifested by symptoms associated with a 70 percent rating (impaired impulse control; difficulty in adapting to stressful circumstances; inability to establish and maintain effective relationships). To the extent that the Veteran reported regular thoughts of not wanting to live during his VA treatment, this is not substantially similar to the symptom of a persistent danger of self-harm, which is contemplated by the 100 percent criteria. Cf. Bankhead v. Shulkin, 29 Vet. App. 10, 19 (2017). The Veteran regularly denied suicidal ideation, intent, or a plan involving self-harm in existing treatment records, and during the May 2012 VA examination. The March 2015 medical opinion on service-connected impairments found that the Veteran's mental problems would cause significant occupational impairment including missed work, inability to focus, and inappropriate responses to normal pressures and constructive criticism of a job. This was sufficient to establish total occupational impairment, which formed the basis for the award of total disability rating based on individual unemployability due to service-connected disability (TDIU). Nevertheless, he was not totally socially impaired. Although he reported relationship difficulties, including specific conflicts with his son and son-in-law, and some marital difficulties, he married the appellant shortly before the appeals period and lived with her until his death. Thus, while the Veteran's PTSD did cause social impairment, including significant deficiencies in most family relations, total social impairment was not shown. In the presence of such a close relationship, affirmatively opposes the notion of total social impairment. Thus, the Board finds that the preponderance of evidence shows that the severity, frequency, and duration of the Veteran's symptoms was not so severe as to result in total social impairment. Thus, the criteria for a 100 percent rating have not met and the appeal must be denied. 2. A rating higher than 20 percent for type 2 diabetes with nephropathy, erectile dysfunction, and right lower extremity peripheral vascular disease The Veteran was originally granted service connection for type II diabetes in May 2011 rating decision, which also granted service connection for peripheral neuropathy of the bilateral upper and lower extremities. At that time, the Veteran's diabetes was rated 20 percent effective May 5, 2011. Each of the upper extremities was also rated 20 percent and each of the lower extremities was also rated 10 percent, all effective May 5, 2011. In the January 2013 rating decision, the RO recharacterized this issue to include nephropathy, erectile dysfunction, and right lower extremity peripheral vascular disease based on noncompensable diabetic complications. An April 2015 decision review officer (DRO) decision granted an earlier effective date of May 29, 2007 for the grant of service connection for diabetes mellitus type II. Diagnostic Code 7913 provides a structured scheme of specific, successive, cumulative criteria. Each higher rating includes the same criteria as the lower rating plus distinct new criteria. Middleton v. Shinseki, 727 F.3d 1172, 1178 (Fed. Cir. 2013). A 10 percent rating is warranted when diabetes is manageable by restricted diet only. A 20 percent rating is warranted when diabetes requires one or more daily injection of insulin and restricted diet, or an oral hypoglycemic agent and restricted diet. A 40 percent rating is warranted when it requires one or more daily injection of insulin, restricted diet, and regulation of activities. Regulation of activities is defined as avoidance of strenuous occupational and recreational activities. A 60 percent rating is warranted when diabetes requires one or more daily injection of insulin, restricted diet, and regulation of activities with episodes of ketoacidosis or hypoglycemic reactions requiring one or two hospitalizations per year or twice a month visits to a diabetic care provider, plus complications that would not be compensable if separately evaluated. A 100 percent rating is warranted when diabetes requires more than one daily injection of insulin, restricted diet, and regulation of activities, with episodes of ketoacidosis or hypoglycemic reactions requiring at least three hospitalizations per year or weekly visits to a diabetic care provider, plus either progressive loss of weight and strength or complications that would be compensable if separately evaluated. Compensable complications of diabetes are evaluated separately unless they are part of the criteria used to support a 100-percent evaluation. Noncompensable complications of diabetes are considered part of the diabetic process. 38 C.F.R. § 4.119, Diagnostic Code 7913 (Note 1). Because Diagnostic Code 7913 contains successive criteria, the criteria for the lower rating must be met before a higher disability rating may be awarded. A higher rating cannot be granted based on a finding that the Veteran's disability picture more nearly approximates the criteria for the next higher rating. However, reasonable doubt regarding the presence of a criterion may be resolved in the Veteran' favor. Johnson v. Wilkie, 30 Vet. App. 245 (2018). The question in this appeal is whether the Veteran's diabetes mellitus required one or more daily injections of insulin, restricted diet, and regulation of activities. Regulation of activities is defined as avoidance of strenuous occupational and recreational activities. This criterion requires medical evidence. Camacho v. Nicholson, 21 Vet. App. 360, 364-65 (2007). VA treatment records show that the Veteran treated his diabetes with oral medications and insulin injections and that he was counseled on his diet and subsequently switched to a sugar substitute and a low-carb diet. These records also reflect diagnoses of erectile dysfunction and peripheral neuropathies. The May 2011 VA diabetes examination notes that the Veteran was taking injectable insulin. He had occasional hypoglycemia rapidly responsive to oral nutrition. He had not had to see a physician or emergency department in the prior twelve months for this and had not had ketoacidosis. He had not been instructed to avoid or modify his activities to avoid hypoglycemia. He also had peripheral neuropathy of the bilateral upper and lower extremities. His upper extremity peripheral neuropathy was described as moderately severe with symptoms including loss of sensation in palms, fingers, and thumbs; weakened grip strength; numbness; tingling; and itching sensation. Nevertheless, his fists were complete and he had no muscle atrophy. His bilateral lower extremity peripheral neuropathy was described as moderately severe on both sides with symptoms including absent reflexes, loss of vibratory and light touch sensation, numbness, tingling, and burning. He had an ataxic gait. The November 2011 diabetes mellitus disability benefits questionnaire (DBQ) shows diagnoses of diabetes mellitus type II, erectile dysfunction, peripheral neuropathy of all extremities, and peripheral vascular disease of the right lower extremity. The Veteran's diabetes was managed with restricted diet, prescribed oral hypoglycemic agents, and prescribe insulin more than one injection per day. The Veteran reported regulation of activities, including no lifting or running, he was out of energy all the time. He felt like he was going to fall down when walking and was unbalanced. He had pain in both feet, joints, and have to wear orthotics and pain in other areas like hips and backs. He had a lot of problems with over urination, frequently wetting his pants. His diabetes affected his love life. He sought diabetic care twice per month. He had not been hospitalized for any episodes of ketoacidosis or hypoglycemic reactions in the prior 12 months. He had not had any progressive unintentional weight loss attributable to diabetes. He had had progressive loss of strength attributable to diabetes. His complications of diabetes mellitus include diabetic peripheral neuropathy, erectile dysfunction, and peripheral vascular disease. He did not have any associated scars or other pertinent physical findings, complication, conditions, signs, and/or symptoms. His diabetes mellitus did not impact his ability to work. The November 2011 artery and vein conditions DBQ notes that the Veteran reported worsening leg cramps since 1995. He had mild right peripheral vascular disease with an ankle-brachial index of .92. This examiner did not note claudication with walking any distance or diminished peripheral pulses. His vascular condition impacted the Veteran's ability to work in a position that required prolonged walking, but did not affect sedentary employment. The November 2011 kidney conditions DBQ notes no current complaints associated with diabetic nephropathy. There was an incidental finding of 1+ protein in urinalysis on this evaluation. The Veteran had renal dysfunction characterized by recurring proteinuria. He did not require dialysis. He did not have kidney, ureteral, or bladder calculi; recurrent urinary tract or kidney infections; kidney transplant or removal; or benign or malignant neoplasm or metastases related to a kidney condition. He did not have any associated scars or other pertinent physical findings, complications, conditions, signs, or symptoms. His kidney condition did not impact his ability to work. The November 2011 genitourinary conditions DBQ shows erectile dysfunction that prevented the Veteran from achieving an erection sufficient for penetration and ejaculation with or without medication. The Veteran did not treat this with continuous medication. He had not had an orchiectomy. He did not have a voiding dysfunction; a history of recurrent symptomatic urinary tract or kidney infection; retrograde ejaculation; a history of chronic epididymitis, epididymo-orchitis, or prostatitis; or a benign or malignant neoplasm or metastases related to a genitourinary condition. Physical examination found normal penis, testes, and epididymis. The Veteran's prostate was not examined because it was not relevant to this condition. He did not have any associated scars or other pertinent physical findings, complications, conditions, signs, or symptoms. His kidney condition did not impact his ability to work. The November 2011 peripheral nerves conditions DBQ notes the Veteran's complaints of numbness and tingling in his bilateral hands and feet. His symptoms included mild paresthesias and/or dysesthesias and numbness of the bilateral upper extremities and moderate paresthesias and/or dysesthesias and numbness of the bilateral lower extremities. Muscle strength testing was normal throughout. He did not have muscle atrophy. His reflexes were normal throughout. He had decreased sensation in the bilateral forearms, hands, fingers, lower legs, ankles, feet, and toes. He did not have any trophic changes attributable to peripheral neuropathy. His gait was normal. This examiner found mild incomplete paralysis of the bilateral radial, median nerves, and ulnar nerves and moderate incomplete paralysis of the sciatic nerves. He did not use an assistive device as a normal mode of locomotion. His peripheral nerve conditions did not result in functional impairment of an extremity such that no effective function remained other than that which would be equally well served by an amputation with prosthesis. He did not have any associated scars or other pertinent physical findings, complications, conditions, signs, or symptoms. His peripheral nerves disabilities impacted the Veteran's ability to work due to difficulty standing and walking, which affected physical employment, but did not affect sedentary employment. The Board finds that the Veteran's diabetes mellitus required only restricted diet, an oral glycemic agent, and one or more daily injection of insulin during the period on appeal. The Veteran was competent to report his reduction in activities due to diabetes, and his reports are credible. Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007). However, the medical evidence of record is against a finding that regulation of activities was required during the period on appeal. The Veteran's diabetes has resulted in the following complications: peripheral neuropathy of the bilateral upper and lower extremities, nephropathy, erectile dysfunction, right lower extremity peripheral vascular disease, and diabetic retinopathy. The Veteran's peripheral neuropathy of the bilateral upper extremities is rated under hyphenated diagnostic code 7913-8514 and his peripheral neuropathy of the bilateral lower extremities is rated under hyphenated diagnostic code 7913-8520. Hyphenated diagnostic codes are used when a rating under one DC requires use of an additional DC to identify the basis for the evaluation assigned; the additional code is shown after the hyphen. 38 C.F.R. § 4.27. In this case, DC 7913 is the diagnostic code for diabetes mellitus. DC 8154 and DC 8520 provide rating criteria for radial and sciatic nerves, respectively, based on severity of disability. The words "mild," "moderate," and "severe" as used in the various Diagnostic Codes are not defined in the Rating Schedule. Regulations provide that ratings for peripheral neurological disorders are to be assigned based the relative impairment of motor function, trophic changes, or sensory disturbance. 38 C.F.R. § 4.120. Consideration is also given for loss of reflexes, pain, and muscle atrophy. See 38 C.F.R. §§ 4.123, 4.124. The term "incomplete paralysis" indicates a degree of lost or impaired function substantially less than the type picture for complete paralysis given with each nerve, whether due to varied level of the nerve lesion or to partial regeneration. When the involvement is wholly sensory, the rating is for the mild, or at most, the moderate degree. The disability ratings for the peripheral nerves are for unilateral involvement; when bilateral, the ratings combine with application of the bilateral factor. 38 C.F.R. § 4.124a, Note at "Diseases of the Peripheral Nerves." The Note to 38 C.F.R. § 4.124a establishes a maximum disability rating for conditions that are wholly sensory, as opposed to a minimum disability rating for conditions that are more than wholly sensory. See Miller v. Shulkin, 28 Vet. App. 376 (2017). The Veteran's bilateral upper extremity peripheral neuropathy was characterized by numbness, tingling, decreased sensation, and conflicting findings regarding grip strength. He had no muscle atrophy or trophic changes. Although the May 2011 examiner characterized these disabilities as moderately severe, the record does not support that characterization. Despite that examiner's finding of reduced grip strength, the Veteran was still able to make a complete fist and he had no muscle atrophy. Moreover, the Veteran's symptoms were entirely sensory mere months later in the November 2011 examination, and his muscle strength was normal. The Veteran's current 20 percent ratings are based on mild incomplete paralysis of the radial nerve. While the record suggests additional nerve involvement, the rating for mild incomplete paralysis of all radicular groups would also warrant bilateral 20 percent ratings under DC 8512. See 38 C.F.R. § 4.124a. Therefore, the Board will not disturb these ratings. The Veteran's bilateral lower extremity peripheral neuropathy was characterized by numbness, tingling, decreased sensation, and conflicting findings regarding reflexes. While the May 2011 examination notes absent reflexes, the November 2011 examiner found his reflexes completely normal. Despite the examiners' characterization of these disabilities as moderate or moderately severe. He had normal muscle strength, no muscle atrophy, and no trophic changes. This is consistent with the 10 percent ratings assigned for mild incomplete paralysis of the sciatic nerve under DC 8520. As the record continues to support the existing ratings for these disabilities, the Board will not disturb them. The rating schedule does not provide a diagnostic code for rating erectile dysfunction (the inability to maintain an erection). However, a compensable evaluation is available for penile deformity under Diagnostic Code 7522, which provides for a 20 percent rating when both deformity and loss of erectile power are present. 38 C.F.R. § 4.115b, Diagnostic Code 7522. This is the highest rating available under Diagnostic Code 7522. A penile deformity is a distortion of the penis, either internal or external. See Williams v. Wilkie, 30 Vet. App. 134, 138 (2018). Here, the record does not show any penile deformity. Thus, a noncompensable rating is warranted for erectile dysfunction and so a separate compensable rating is not warranted for this disability. Under DC 7541, diabetic nephropathy is rated as renal dysfunction. See 38 C.F.R. § 4.115b. A compensable (30 percent) rating for renal dysfunction requires albumin constant or recurring with hyaline and granular casts or red blood cells; or, transient or slight edema; or, hypertension at least 10 percent disabling under diagnostic code 7101. 38 C.F.R. § 4.115b, Diagnostic Code 7541. Here, the record does not show any of these symptoms. Thus, a noncompensable rating is warranted for diabetic nephropathy and so a separate compensable rating is not warranted for this disability. Peripheral vascular disease is rated under DC 7114 for arteriosclerosis obliterans. See 38 C.F.R. § 4.104. A compensable (20 percent) rating under the diagnostic code requires claudication on walking more than 100 yards, and diminished peripheral pulses or ankle/brachial index of 0.9 or less. 38 C.F.R. § 4.104, DC 7541. Here the record does not show any of these symptoms. While his ankle/brachial index was low, it remained above 0.9. Thus, a noncompensable rating is warranted for right lower extremity peripheral vascular disease and so a separate compensable rating is not warranted for this disability. His diabetic retinopathy rating is addressed separately below. Accordingly, the preponderance of the evidence is against assigning a rating in excess of 20 percent during the period on appeal. 3. A compensable rating for diabetic retinopathy The Veteran was originally granted service connection for diabetic retinopathy in the January 2013 rating decision on appeal. During the pendency of the appeal, VA issued a final rule revising the portion of the VA Schedule for Rating Disabilities that addresses the organs of special sense and schedule of ratings-eye. 89 Fed. Reg. 15,316 (Apr. 10, 2018). The final rule went into effect May 13, 2018. Where there is a change in the rating criteria during the appeal period, the Board will consider the claim in light of both the former and revised schedular rating criteria, although an increased evaluation based on the revised criteria cannot predate the effective date of the amendments. Under the former criteria, retinopathy (DC 6006) is rated under the General Rating Formula for Diagnostic Codes 6000 through 6009. The General Rating Formula instructs to evaluate on the basis of either visual impairment due to the particular condition or on incapacitating episodes, whichever results in a higher evaluation. Where incapacitating episodes have a total duration of at least 1 week, but less than 2 weeks, during the past 12 months, a 10 percent rating is warranted. Where incapacitating episodes have a total duration of at least 2 weeks, but less than 4 weeks, during the past 12 months, a 20 percent rating is warranted. Where incapacitating episodes have a total duration of at least 4 weeks, but less than 6 weeks, during the past 12 months, a 40 percent rating is warranted. Where incapacitating episodes have a total duration of at least 6 weeks during the past 12 months, a 60 percent rating is warranted. A Note following the General Rating Formula indicates that, for VA purposes, an incapacitating episode is a period of acute symptoms severe enough to require prescribed bed rest and treatment by a physician or other healthcare provider. Under the revised criteria, retinopathy (DC 6006) is rated under the General Rating Formula for Diseases of the Eye. The General Rating Formula instructs to evaluate on the basis of either visual impairment due to a particular condition or on incapacitating episodes, whichever results in a higher evaluation. Where there are documented incapacitating episodes requiring at least 1 but less than 3 treatment visits for an eye condition during the past 12 months, a 10 percent rating is warranted. Where there are documented incapacitating episodes requiring at least 3 but less than 5 treatment visits for an eye condition during the past 12 months, a 20 percent rating is warranted. Where there are documented incapacitating episodes requiring at least 5 but less than 7 treatment visits for an eye condition during the past 12 months, a 40 percent rating is warranted. Where there are documented incapacitating episodes requiring 7 or more treatment visits for an eye condition during the past 12 months, a 60 percent rating is warranted. Note (1) indicates that, for the purposes of evaluations under 38 C.F.R. § 4.79, an incapacitating episode is an eye condition severe enough to require a clinic visit to a provider specifically for treatment purposes. Note (2) indicates that examples of treatment may include but are not limited to: systemic immunosuppressants or biologic agents; intravitreal or periocular injections; laser treatments; or other surgical interventions. Note (3) indicates that, for the purposes of evaluating visual impairment due to a particular condition, refer to 38 C.F.R. § 4.75-4.78 and to § 4.79, DCs 6061-6091. The criteria for visual impairment, including impairments of visual acuity, visual fields, and/or muscle function, have remained unchanged. Impaired visual acuity is rated under diagnostic codes 6061-6066 based on the best corrected distance vision. 38 C.F.R. §§ 4.76, 4.79. Impairment of visual fields are rated under DC 6080-6081 based on the average concentric contraction of the visual field of each eye; asymmetric impairments are converted to their visual acuity equivalents. 38 C.F.R. §§ 4.77, 4.79. Impaired muscle function is rated under DC 6090-6091 with an evaluation for diplopia being assigned to only one eye. 38 C.F.R. §§ 4.78, 4.79. VA treatment records show mild background diabetic retinopathy, refractive errors, blepharitis, posterior vitreous detachment, and pseudophakia bilaterally. The January 2013 eye conditions DBQ shows diagnoses of background diabetic retinopathy, cataracts, and pseudophakia. The Veteran had a history of laser surgery and cataract surgery in both eyes. He saw floaters in his vision and the back of his eyes felt sore at times. His bilateral distance visual acuity was 20/40 or better with ot without correction. His uncorrected near vision was 20/70 bilaterally, correctable to 20/40 or better. His pupils were round and reactive to light. No pupillary defect was present. He did not have anatomical loss, light perception only, extremely poor vision, or blindness of either eye. He did not have a corneal irregularity that resulted in severe irregular astigmatism or diplopia. Physical examination found grade-1 blepharitis, clear posterior intraocular lens implants, and small dot hemorrhages in the midperiphery of the retina bilaterally. He had a visual field defect, but not contraction of a visual field or loss of a visual field. The accompanying visual field perimeter chart showed some loss of visual field as described below: Meridian Normal Right Eye Left Eye Up 45 23 25 Up temporally 55 25 40 Temporally 85 52 62 Down temporally 85 52 53 Down 65 30 40 Down nasally 50 27 27 Nasally 60 25 27 Up nasally 55 20 37 Total: 500 254 311 Average Concentric Contraction 62.5 31.75 38.875 He had a scotoma affecting at least one-quarter of the visual field of his right eye. He did not have legal (statutory) blindness based upon visual field loss. He had bilateral postoperative cataracts with replacement intraocular lenses, but not aphakia or dislocation of the crystalline lens. His diabetic retinopathy had created a narrowing of the visual field nasally in the right eye. He did not have scarring or disfigurement attributable to any eye condition. In the prior twelve months, he had not had any incapacitating episodes attributable to any eye conditions. His eye conditions did not impact his ability to work. Based on the above, the Veteran's diabetic retinopathy manifested as a right-eye scotoma and visual field loss with average concentric contraction of 32 degrees in the right eye and 39 degrees in the left eye. The Veteran's right-eye scotoma warranted a minimum 10 percent rating under DC 6081, with higher ratings available for visual field impairment. See 38 C.F.R. § 4.79. His bilateral visual field loss warranted a 30 percent rating under DC 6080, which is higher than the minimum rating for scotoma. As such, a 30 percent rating is warranted for visual field loss. The Veteran has no other visual impairment as his corrected visual acuity was consistently 20/40 or better, and he had no impairment of muscle function. Similarly, he has had no incapacitating episodes due to his eye disability. Thus, the Veteran's diabetic retinopathy was consistent with a 30 percent rating, but not higher, and, to that extent, the appeal is granted. Service Connection 4. Service connection for hypertension The Veteran contended that his hypertension was causally related to his exposure to herbicide agents during his service aboard the U.S.S. Conway during the Vietnam Era. The Board notes that the Veteran's service aboard the U.S.S. Conway has previously been determined to entitle him to the presumption of exposure to herbicide agents and no further discussion is necessary to establish such exposure. For VA rating purposes, the term hypertension means that the diastolic blood pressure is predominantly 90 millimeters (mm) or greater, and isolated systolic hypertension means that the systolic blood pressure is predominantly 160 mm or greater with diastolic blood pressure of less than 90 mm. 38 C.F.R. § 4.104, DC 7101, Note 1. Certain chronic diseases will be presumed related to service, absent an intercurrent cause, if they were shown as chronic in service; or, if they manifested to a compensable degree within a presumptive period following separation from service; or, if they were noted in service (or within an applicable presumptive period) with continuity of symptomatology since service that is attributable to the chronic disease. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.303, 3.307, 3.309. Walker v. Shinseki, 708 F.3d 1331, 1338 (Fed. Cir. 2013). Additionally, service connection may be presumed for certain enumerated diseases based on exposure to herbicide agents. See 38 U.S.C. § 1116; 38 C.F.R. §§ 3.307, 3.309. However, hypertension is not one such disease. See 38 C.F.R. § 3.309 (e). The Veteran had a current diagnosis of hypertension as evidenced by his VA treatment records and his November 2012, January 2013, and November 2020 disability benefits questionnaires. Hypertension is an enumerated condition under 38 C.F.R. § 3.309(a); Walker, 708 F.3d 1331. However, the disability was not shown as chronic in service, did not manifest to a compensable degree within a presumptive period, and was not noted in service with attributable continuity of symptomatology. The Veteran reported being diagnosed with hypertension in 1977, years after his separation from service and years outside of the applicable presumptive period. This diagnosis is not of record. The medical evidence of record does not suggest a hypertension diagnosis in service or within one year of his separation. Service connection for hypertension may still be granted on a direct basis; however, the preponderance of the evidence is against finding that a medical nexus existed between the Veteran's hypertension and an in-service injury, event, or disease. 38 U.S.C. §§ 1110, 1131; Holton v. Shinseki, 557 F.3d 1363, 1366 (Fed. Cir. 2009); 38 C.F.R. § 3.303. The November 2020 VA opinion found that the Veteran's hypertension did not arise in service or within one year of his separation from service, and was not at least as likely as not related to an in-service injury, event, or disease, including his presumed exposure to herbicide agents in service. The rationale was that Agent Orange has not been shown to cause hypertension. The current, widely accepted, peer-reviewed literature has not established Agent Orange as a cause of hypertension. The NAS study in 2018 suggested an association, but did not establish cause and effect. Current medical knowledge and practice has not established cause and effect. Therefore, it is less likely than not that the Veteran's hypertension is due to or incurred in herbicide/Agent Orange exposure. Neither the Veteran, prior to his death, nor the appellant has submitted a positive medical nexus opinion to refute this opinion. While the Veteran believed his hypertension was related to an in-service injury, event, or disease, including presumed in-service exposure to herbicide agents, he was not competent to provide a nexus opinion in this case. This issue is also medically complex, as it requires specialized medical education to determine pathology after a significant passage of time. Jandreau v. Nicholson, 492 F.3d 1372, 1377, 1377 n.4 (Fed. Cir. 2007). Consequently, the Board gives more probative weight to the competent medical evidence. Alternately, the Board has considered whether service connection for hypertension was warranted as secondary to his service-connected diabetes. Service connection may be granted for a disability that is proximately due to, or aggravated by, service-connected disease or injury. 38 C.F.R. § 3.310. The question for the Board is whether the Veteran has a current disability that is proximately due to or the result of, or was aggravated beyond its natural progress by service-connected diabetes. The Board concludes that, while the Veteran has a current disability, the preponderance of the evidence is against finding that the Veteran's hypertension is proximately due to or the result of, or aggravated beyond its natural progression by service-connected disability. 38 U.S.C. §§ 1110, 1131; Allen v. Brown, 7 Vet. App. 439 (1995) (en banc); 38 C.F.R. § 3.310(a). The November 2011 diabetes mellitus DBQ found that Veteran's hypertension was not at least as likely as not due to or permanently aggravated by his service-connected diabetes. Likewise, his November 2011 kidney conditions DBQ found that the Veteran's hypertension was not due to renal dysfunction or any kidney condition. The November 2020 VA opinion found that the Veteran's hypertension was not at least as likely as not related to his service-connected diabetes. The rationale was that he did not have significant diabetic nephropathy. The 2012 diagnosis was based solely on proteinuria, but at no time did he have elevations of creatine or diminishment of glomerular filtration rate (GFR), which are metabolic measures of renal function. Absent metabolic renal dysfunction, no cause or aggravation can be attributed. The presence of simple proteinuria would not elevate the Veteran's blood pressure. The hypertension likely predated the diabetes though this cannot be completely ascertained. Nonetheless, with normal renal function, it is less likely than not that the Veteran's hypertension was due to or aggravated by his diabetes. Additionally, the Veteran's blood pressure control was stable. Simple changes in medication or dose adjustment do not constitute aggravation beyond its natural course. Hypertension tends to worsen over time. There did not appear to be any progression due to any cause, and certainly not beyond the natural course due to any cause, including the Veteran's diabetes with nephropathy, erectile dysfunction, and right lower extremity peripheral vascular disease. Peripheral vascular disease was due to atherosclerosis and did not significantly impact blood pressure. For the reasons stated above, the Board finds that the preponderance of evidence is against the Veteran's claim of entitlement to service connection for hypertension and his appeal must be denied. There is no reasonable doubt to be resolved as to this issue. See 38 U.S.C. § 5107 (b); 38 C.F.R. § 3.102; Gilbert v. Derwinski, 1 Vet. App. 49 (1990). Joshua Castillo Acting Veterans Law Judge Board of Veterans' Appeals Attorney for the Board B. Houbeck The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.